1. Field of the Invention
The present invention relates generally to testing devices for testing the continuity of lamp circuits and, more particularly, to devices especially adapted for testing the continuity of lamp circuits in trailers.
2. Description of the Prior Art
Tractor trailer combinations generally include a plurality of from, side, and rear lamps. The lamps on the trailer generally receive power from the tractor. The trailer lamps are in circuit with conductors and, generally, a standard 7-pin connector is used to connect the trailer conductors to a complementary connector on the tractor.
For purposes of safety and for conforming to law, the full complement of trailer lamps are tested prior to embarking on a journey. A basic approach to testing trailer lamps is for the truck driver to enter the tractor, start the motor, and back up the trailer while applying the brakes. Simply for the purpose of testing trailer lamps, this procedure is both time consuming and fuel consuming. In this respect, it would be desirable if a trailer lamp testing device were provided which does not require a tractor motor to be started up and does not require trailer to be backed up in order to test the trailer lamps.
When a fleet of tractor trailers must have their trailer lamps tested, the wasted time and expense of starting the respective tractor motors and backing up the respective trailers in the fleet are greatly multiplied. In this respect, it would be desirable if a trailer lamp testing device were provided that permits trailer lamps to be tested in a fleet of trailers in a manner that is much less consuming of time and expense than starting each individual tractor motor and backing up each individual trailer.
Throughout the years, a number of innovations have been developed relating to testing trailer lamp circuits, and the following U.S. patents are representative of some of those innovations: U.S. Pat. Nos. 3,836,843; 4,166,242; 4,249,125; 4,547,722; and 4,884,032.
More specifically, U.S. Pat. Nos. 3,836,843, 4,166,242, and 4,249,125 disclose devices for testing electrical circuits in tractors. Light emitting diodes (LEDs) are used and light up when specific tractor circuits exhibit continuity. The LEDs use power from the tractor when they are lit up. Moreover, the devices in these patents do not readily test trailer lamp circuitry if the trailer is disconnected from the tractor. In this respect, it would be desirable if a trailer lamp testing device were provided which did not use power from the tractor. Moreover, it would be desirable if a trailer lamp testing device can be employed when the trailer is disconnected from the tractor.
U.S. Pat. No. 4,547,722 discloses a test panel for tractor and trailer lights. The test panel has its own battery and a 7-pin connector. If a lamp is burned out, however, there is no provision with this device to provide a replacement lamp. In this respect, it would be desirable if a trailer lamp testing device were provided which stores a number of replacement lamps to facilitate replacement of a lamp that is discovered to be burned out as a result of carrying out a test.
U.S. Pat. No. 4,884,032 discloses a trailer/tractor light testing system which includes its own battery to permit testing of the trailer lamps with the tractor being connected to the trailer. A circular selector switch is provided that enables testing of one lamp circuit at a time. Testing of one lamp circuit at a time has a distinct disadvantage. One may go through a sequence of tests and forget the result of preceding tests. In this respect, it would be desirable if a trailer lamp testing device were provided which provided testing of all the lamp circuits simultaneously.
Still other features would be desirable in a trailer lamp testing and lamp storage apparatus. For example, although a 7-pin connector is substantially standardized, there may be other connectors that have different numbers of pins. There is currently under development a 13-pin connector that can be used for "smart" trailers which have computerized subsystems in the trailer. In this respect, it would be desirable if a trailer lamp testing device were provided that is adaptable to 13-pin connectors for testing the circuits served by the 13-pin connector.
As stated above, it would be desirable if a trailer lamp testing apparatus also included a lamp storage portion to facilitate replacement of burned out lamps. Replacement lamps must make good electrical contact for the lamps to function properly. In environments subjected to wide temperature ranges in which metal electrical contacts expand and contract, metal contacts are often provided with pasty conductive material to facilitate electrical contact between metal contacts. In this respect, it would be desirable if a trailer lamp testing and lamp storage device were provided which included a supply of a pasty electrical conductive material so that the metal contacts on the lamps can be provided with the electrically conductive paste.
Another inhibitor of good electrical contact is the present of metal oxide particles or metal oxide films covering a base metal. The oxides are relatively nonconductive compared to the base metal. One way of removing metal oxides from base metals is to use an abrasive to abrade away the metal oxide. In this respect, it would be desirable if a trailer lamp testing and lamp storage device were provided which included a quantity of an abrasive material for removing metal oxide films from base metal on lamp contacts.
When storing a plurality of replacement lamps, an organized manner of storage is preferred over a random disorganized conglomeration of different lamps. In this respect, it would be desirable if a trailer lamp testing and storage device were provided which includes an organized arrangement for storing replacement lamps.
Thus, while the foregoing body of prior art indicates it to be well known to use testing devices for trailer lamps, the prior art described above does not teach or suggest a trailer lamp testing and lamp storage apparatus which has the following combination of desirable features: (1) does not require a tractor motor to be started up and does not require trailer to be backed up in order to test the trailer lamps; (2) permits trailer lamps to be tested in a fleet of trailers in a manner that is much less time consuming and expensive than starting each individual tractor motor and backing up each individual trailer; (3) does not use power from the tractor; (4) can be employed when the trailer is disconnected from the tractor; (5) stores a number of replacement lamps to facilitate replacement of a lamp that is discovered to be burned out as a result of carrying out a test; (6) provides testing of all the lamp circuits simultaneously; (7) is adaptable to 13-pin connectors for testing the circuits served by the 13-pin connector; (8) includes a supply of a pasty electrically conductive material so that the metal contacts on the lamps can be provided with a quantity of electrically conductive paste; (9) includes a quantity of an abrasive material for removing metal oxide films from base metal on lamp contacts; and (10) includes an organized arrangement for storing replacement lamps. The foregoing desired characteristics are provided by the unique trailer lamp testing and lamp storage apparatus of the present invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.